About half of newborn congenital hearing loss has a genetic cause. Identifying genes involved in hearing loss is essential for precise diagnosis, genetic counseling and future treatment of this common abnormality. Through the Developmental Genome Anatomy Project (DGAP, dgap.harvard.edu), we have identified a subject with various developmental disorders including congenital hearing loss and early onset prostate cancer, whose de novo chromosomal translocation interrupts an unannotated gene, C2orf43. The goal of this proposal is to investigate the possible role of C2orf43 in hearing to extend my background in hearing physiology with genetics training. I will analyze the phenotype-genotype correlation between hearing loss and C2orf43 in humans by further characterizing the subject's hearing loss, excluding other known genetic causes for the hearing loss, and screening hearing loss populations for variations in C2orf43. Human subjects research will be complemented by studies of genotype-phenotype correlation in zebrafish and a newly developed C2orf43 knockout (KO) mouse model and focused on changes in expression, morphology and physiology in the ear and other organ systems. The proposed study should allow us to validate that C2orf43 is necessary for normal hearing, shed light on the role of C2orf43 in hearing physiology, develop methods to analyze other genes associated with hearing loss, and establish a genetics research background in a young hearing investigator.